reverse-lookup illegal? - dumb law (Re: semi-public data?? (Re: phone lookups))

[Adam Back]

On Wed, Jun 26, 2002 at 03:48:53AM +0100, Peter Fairbrother wrote:
> Adam Back wrote:
> > if it's public it's public -- no semi-public, or public but only to
> > people who pay 200 pounds, or public to people who show up at an
> > office.
> 
> There is an unmentioned difference here, brought about partly by the
> development of computer search programs, although the distinction existed
> before. Information is useless unless it is *looked at.
> 
> Anyone can look up someone's number in a telephone directory, from knowing
> who that someone is, but it is illegal in the UK to look up the someone from
> a number.

If that is the case, that law is stupid.  In a computerised world one
implies the other.  Use the lookup by name from electoral role or
other, reconstruct the database, put it on the web and lookup reverse
numbers to your hearts content.

> [I could** devise a cryptographic solution to implement the one-way nature
> of the public perception of telephone directory lookups, but unfortunately
> at a cost that would be enormous, involving a change to the way the phone
> number system works. This won't happen in real life.]

Not so easy I think, unless you get a different number each time you
look it up which would make numbers incoveniently large, with out
that, the above attack still works.

Adam